<?php

if (!defined('BASEPATH'))
    exit('No direct script access allowed');
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP 5.1.6 or newer
 *
 * @package		CodeIgniter
 * @author		ExpressionEngine Dev Team
 * @copyright	Copyright (c) 2006 - 2014 EllisLab, Inc.
 * @license		http://codeigniter.com/user_guide/license.html
 * @link		http://codeigniter.com
 * @since		Version 2.0
 * @filesource
 */
// ------------------------------------------------------------------------

/**
 * CodeIgniter Memcached Caching Class
 *
 * @package		CodeIgniter
 * @subpackage	Libraries
 * @category	Core
 * @author		ExpressionEngine Dev Team
 * @link
 */
class CI_Cache_file extends CI_Driver {

    protected $_cache_path;

    /**
     * Constructor
     */
    public function __construct() {
        $CI = & get_instance();
        $CI->load->helper('file');

        $path = $CI->config->item('cache_path');

        $this->_cache_path = ($path == '') ? APPPATH . 'cache/' : $path;
    }

    // ------------------------------------------------------------------------

    /**
     * Fetch from cache
     *
     * @param 	mixed		unique key id
     * @return 	mixed		data on success/false on failure
     */
    public function get($id) {
        if (!file_exists($this->_cache_path . $id)) {
            return FALSE;
        }

        $data = read_file($this->_cache_path . $id);
        $data = unserialize($data);

        if (time() > $data['time'] + $data['ttl']) {
            unlink($this->_cache_path . $id);
            return FALSE;
        }

        return $data['data'];
    }

    // ------------------------------------------------------------------------

    /**
     * Save into cache
     *
     * @param 	string		unique key
     * @param 	mixed		data to store
     * @param 	int		length of time (in seconds) the cache is valid
     * 					- Default is 60 seconds
     * @return 	boolean		true on success/false on failure
     */
    public function save($id, $data, $ttl = 60) {
        $contents = array(
            'time' => time(),
            'ttl' => $ttl,
            'data' => $data
        );

        if (write_file($this->_cache_path . $id, serialize($contents))) {
            @chmod($this->_cache_path . $id, 0777);
            return TRUE;
        }

        return FALSE;
    }

    // ------------------------------------------------------------------------

    /**
     * Delete from Cache
     *
     * @param 	mixed		unique identifier of item in cache
     * @return 	boolean		true on success/false on failure
     */
    public function delete($id) {
        return unlink($this->_cache_path . $id);
    }

    // ------------------------------------------------------------------------

    /**
     * Clean the Cache
     *
     * @return 	boolean		false on failure/true on success
     */
    public function clean() {
        return delete_files($this->_cache_path);
    }

    // ------------------------------------------------------------------------

    /**
     * Cache Info
     *
     * Not supported by file-based caching
     *
     * @param 	string	user/filehits
     * @return 	mixed 	FALSE
     */
    public function cache_info($type = NULL) {
        return get_dir_file_info($this->_cache_path);
    }

    // ------------------------------------------------------------------------

    /**
     * Get Cache Metadata
     *
     * @param 	mixed		key to get cache metadata on
     * @return 	mixed		FALSE on failure, array on success.
     */
    public function get_metadata($id) {
        if (!file_exists($this->_cache_path . $id)) {
            return FALSE;
        }

        $data = read_file($this->_cache_path . $id);
        $data = unserialize($data);

        if (is_array($data)) {
            $mtime = filemtime($this->_cache_path . $id);

            if (!isset($data['ttl'])) {
                return FALSE;
            }

            return array(
                'expire' => $mtime + $data['ttl'],
                'mtime' => $mtime
            );
        }

        return FALSE;
    }

    // ------------------------------------------------------------------------

    /**
     * Is supported
     *
     * In the file driver, check to see that the cache directory is indeed writable
     *
     * @return boolean
     */
    public function is_supported() {
        return is_really_writable($this->_cache_path);
    }

}

/* End of file Cache_file.php */
/* Location: ./system/libraries/Cache/drivers/Cache_file.php */